TMJDS (temporomandibular joint dysfunction syndrome) is an umbrella term covering clinical manifestations due to disfunction of the jaw joint and the muscles that control the jaw. The prevalence of this condition is high amongst the general population, with many studies showing at least 40% of the population presenting with at least one clinical manifestations and around 25% presenting with symptoms. Signs and symptoms may include jaw joint sounds, a limitation in mouth opening, pain in or about the ears (the jaw joint), locking of the jaw and pain when chewing. TMJDS symptoms may be exacerbated during times of stress and may be related to nocturnal tooth clenching or grinding. They may be caused by parafunction- using the jaw in ways it is not designed such as chewing pens, gums or biting the nails. Treatment of the condition may involve attempting to eliminate stress and any parafunctional habits, performing specific exercises, wearing a splint or using an appliance that fits within the ear canal (Cerezen treatment).

A splint is a plastic covering for the teeth which is usually worn during sleep. It is worn to prevent pain associated with grinding your teeth during sleep.

There are various types of splint which can be fabricated. They aim to reduce damage caused to teeth by grinding, to align the lower jaw in a more favourable position and to balance the contacts between the upper and lower teeth. They all aim to reduce symptoms associated with TMJDS.

Cerezen is a recent innovation in the treatment of TMJDS. Cerezen was first developed in the USA and was introduced to the UK in 2015. Cerezen treats TMJDS in an entirely different way to the traditional approach of splints. The Cerezen device is a 3d printed hollow plastic tube which custom fits inside your ear canal. It can be worn for almost 24 hours per day, is virtually invisible, does not limit your hearing and does not impact on your normal daily activities such as eating. The device is far less obtrusive than traditional splints. Cerezen, like many great inventions, was discovered accidentally. An audiologist made a hearing aid which was slightly too large for the patients ear canal. At review, it was noted that their TMJDS symptoms had all but resolved. From this, further development and research lead to the inception of Cerezen. Cerezen works because when the jaw is clenched, the ear canal distorts. By making the device fit the ear canal when the jaw is relaxed, it becomes slightly uncomfortable to clench when the device is in position. In This way Cerezen discourages the patient from clenching. A recent study and a preliminary audit, conducted at Birmingham university, indicate that Cerezen is at least as effective as a Michigan splint (the gold standard treatment) at combating the symptoms of TMJDS.